Coal drying



April 5, 19276,

o.-w. RANDOLPH GOAL DRYING Filed Deb. 24. 1923 4 Sheet-Sheet 1 L -/1 1ry as .GMMPMMQ TTB NE Y April 5, 1927.

336%,3; 0. W. RANDOLPH v I COAL DRYING Filed Dec. 24; 1525 4 Sheets-Sheet? MMLMRQ L A URNEY April 5,1927.

'0. w; RANDOLPH COAL mums Filed Dec; 24. 1923 4 heets-Shet 4 fig 8 i:

'l r IIIIIIII/I/I ll/llI/II/lIII/111M BY A Patented Apr; 5, 1927. i l mrro STATES 1,623,553- PATENT} OF OLIVER w. RANDOLPH, or TOLEDO, onro.

.. COAL DRYING.

Application filed December 24, 1923. Serial No. 682,489.

' This invention relates to treatment of material, more especially in astream for the removal of moisture therefrom.

This invention has utility in the drying of, granular material, as coalwhen crushed so asto pass through a two inch mesh screen.

The method and apparatus are also of value in the drying of grain'andother materials. Referring to the drawings:

Fig. 1 is a side elevation of an installation embodying features of theinvention v herein disclosed as a coal drier;

some details;

Fig. 2 is a section on an enlarged scale on the line II II,;Fig. 1;

Fig. 3 is a view as from the left of Fig. 1 of; a structure departingfrom Fig. 1 in Fig. 4 is a planview ofthe drier of Fig. 3,

with the supply hoppers removed;

Fig. 5 is asection on the line VV, Fig. 3, SllOWll'l in plan the, flowequalizing d1scharge ioppers and blower;

Fig. 6 is a perspective view of a sectlon or. unit-as for assembl into adrier housing;

Fig. '7 is a view through a drier transversely of the deflectors or ductsections, and

' similar to Fig. 2, but showing the staggered sections of thehorizontal series adjacent, instead of spaced as in Fig. 2; and

; Fig. 8 is a section on the line VIII-VIII,

gupply hopper 1,say for crushed coal as coming from the crusher and ofsizes not ex-- ceeding two inches in diameter, has a lurality ofdischarge legs 2 for more uni ormly delivering the flowing wet coal as astrea'm or .streams to the drier herein disclosed. The drier structureis herein shown as having uprights 3 as a crate in which are assembledthe units. The normal unit (Fig. 6) is shown as having a gable orinverted V-shaped, divider ortion 4 from which downwardly extend sides 5to deflector the flowing material against non-treating regions ofthe-housing. To this end half trough sections or units are provided.These semi-units have half gable portions 10,

(Figs. 2, 7) to side portions 5 terminating in deflector portions 6. Theopposite half orside of the inverted trough or open bottom duct iscompleted by wall 11 terminating in flange portions 12, 13, for assemblyby bolts 14. In the grouping wherein these half sections or semi-unitsare continuous vertically in providing the housing sides (Fig-I 2), astaggered groupin is obtained by providing extensions 15 or unit endmembers or supports downward beyondthe extent normally of the members 7,8. These extension downward units are alternated I along the bottom rowor for providing a secondseries or horizontal row ]11St up from thebottom or final deflector series of sec-' tions. As herein disclosed thecolumns are vertical. The half sections are rights and lefts. The fullsections may be assembled in the structure either end to. It accordinglyfollows the openings through the trough supports may be upon oppositesides of the structure. This is a grouping definitely taken. intoaccount herein. I

The loose flowing stream of the granular material tumbles into the upperportion of the drier, upon gables 4 and half gables 10.

The gables' divide the stream as passing downward from the tophorizontal'series of sections. Parallel thereto and therebelow, is asucceeding horizontal series of sections, the gables 4 of which dividethe stream portions as deflected theretoward by the deflectors 6. Thethird horizontal series is similarto the first series, "and with lowangle of repose or such proportioning between upper deflectors 6 andsucceeding gable 4 therebelowas will permit inflow of the stock ormaterial to submerge such gable 4, there is a recombining of adjacentsubdivisions of the flow for again encountering subdivisions .Which mayresult in the zigzag vertically extending streams more or less spillinginto each other in the descent. 1 The vertical extent of the housing,not only as to the size zontal series as alternating, may be varied torespond to the rate of flow of the material, the character of thematerial, the extent of treatment to be given the material, as well asthe velocity of the treating medium. When such medium is air to act as adrier,

of the sections, but as to the number'of horiits dryness or lack ofhumidity and its temperature are factors.

The air supply is preferably warmed, and the treating medium may be fluegases. Such hot air supply is here shown as conducted by pipe to blower16 which-is driven by belt 17 upon pulley 18 of the blower.

From this blower 16 upwardly extends riser 19 along the side of thehousing -pro- ,The second horizontal seriesof sections.

in Fig. 2 shown as the sections having the extensions 15, have thesupports 8 withthe to air escape as ag openings 9 therethrough on theopposite side or end of the drier from the riser 19.

This second horizontal series of sections and alternating horizontalseries of sections thereover, have their openings 9 on this same side orend and in commnnication with air escape passage 20. Accordinglyalternating horizontal series of sections are similarly connected,while'adjacent horizontal series are connected one to air supply and theother The gas or air flow from an open bottom air supply duct passesfrom an pen bottom duct around the edge of the deflectors 6. Such airmay not hug the outside walls of the inverted trough and by moving upthe side 5 to the gable portions 4, 10, keep in through the drier, theair, as coming or flowing-lrom a supply duct and out from under adeflector 6, must travel transversely through a stream or stream sectionto get under a deflector 6 of an air escape duct open bottom. Fromthence it is free to move by way of opening 9 to the passage 20.

[As the hot air flow is continuous and the material flow is alsocontinuous, the constant transverse blowing of air through such material, not only effects a drying out action upon each granule onparticle of the naterial in taking up such as humidity in the treatingair, but the finer particles of the -coal are not only removed from theflow-- mg stream but are held in suspension, and

even conveyed into the passage 20. Here the heavier of the entrainedparticles in the less velocity larger way may preci itate out and beconducted by chute 21 an conduit 22 to dry coal delivery-way 23. Thefiner articles'and dust may rise with the coolmg exhaust air in thepassage 20, enter the cyclone dust collector 24-, for escape of thepurified air by way of the outlet 25, while circuit. For completing -itscircuitor continuous.

the collected dust will flow downward from the dust collector into theconduit 22, to. be supplied into the dry coal as traveling in thedelivery way 23. The fuel burning value of theproduct is thus conserved,and the full rangcof sizes in the coal gives the dried product improvedpulverizing advantages.

Some. control of the rate of travel ot'the treated material through theapparatus may be had from the discharge end thereof. The extent upwardof the angle of repose of the stock is broken or subdivided and eventhroughout the drier by the deflectors 6. There is thus reduced thetendency for a jamming at the final outlet with a maintaineddistribution of the flow from the whole apparatus. Adjacent the lowerhorizontal series of sections of the drier is grouped a plurality ofhoppers 26. Granular material as flowing from these hoppers 26 passes tohoppers 27 offset or out of alignment with the hoppers 26 which deliverto discharge outlet hopper 28 in communication with the dried materialreceiving way 23. A valve 29 may be operated by handle 30 for checkingthe flow ofjmaterial from the hopper 28 into the way 23, and therebyell'ec't successive backing up or retarding of the tumbling flow of thestream of material being treated through and from the drier.

While there is a wide field for the use of the apparatus of thisdisclosure, and it has exceptional value in the drying of grain,

an instance of theopcration is taken in the removing ofmoisture fromcoal. In a small machine, bituminous coal supplied about at the rate ofone thousand pounds per hour at 57 F. and carrying 10% moisture has beenacted upon by a draft of gases enterin; at about 400 F. and leaving atabout 160 F., to bring the coal up to 212 F. and pull its moisturecontent down to approximately In many types of installation the invertedtroughs and their supports may be formed from sheet metal and welded.into a unit, but asherein shown the supports are of cast material forinterlitt-ing in the vertical assembly.

\Vhile. the staggered horizontal series of the. units or sections ofFig. 2 are shown as vertically overlapping, staggered horizontalrelation is maintained in the assembly of Fig. 7 with the units of eachseries abutting There is maintained the stream dividing action, therecombining, and the general vertical extent of a zigzag descendingstream. There is increased number of hoppers to which the drier directly.delivers, in the apparatus of Figs. 3, 5, 7.

'lhermon1eter 31 (Fig. 1) may serve as a visible check upon thetemperature of the hot gases supplied to the drier. Air com- [pressor 32as driven from" the bliiwer 16 half sections .in completing the sidewalls of the-drier housing.

- In the air escape open bottom ducts, the heavier particles extractedfrom the material treated precipitate out, even before passing out theopenings 9'. Such material air on one side of said stream, creating ahigher pressure for the air on theother side of said stream isolatedfrom said air takeoff by said angle of repose regions in therebysubjecting the stream divisions to fine particle removal and drying by adraft of air into'the ang e of repose'surface regions of said stream,taking draft from the stream at another angle of repose surface regionof said stream, collectin said particles, and delivering the collectedparticles into the stream of the dried coal. I

2. A gas treating; apparatus for flowing stream of divided coal,embodying staggered dividersfor the flowing coal, a gas delivery ductfor supply to. one set of said dividers,

falls on a gable 10 forrecombiningwith the a gas discharge duct for gasand fine partiflow, or falls directly .into the stream.

l/Vhen the drier is put into service, it is good practice to shiftthelever to close the valve 29, and keep it closed until the drier is fullycharged. The valve may then he opened and the degree of opening which itis desirable to maintain accordin to the: various other condltions maybe adopted, and. the structure allowed to run cont1nuouslyandautomatically.

In the crushing of some coals, the dust therein runs as high as 15%, andin accord ance with the mode of not only drying, but reclaiming such(lust for burning, is a material economy. Furthermore, there is notobjectionable dust floating about the plant and neighborhood of theinstallation. With the drier installed in conn'cctiolrwith a fuelconsuming plant, there is heat economy in the drier operation by usingthe flue gases from the fuel consuming plant.

The structure of the apparatus as herein disclosed is for the warm airto travel upward from an intake to an air escape of outlet duct series.This takesadvantage of the natural draft tendency of the warm gases.However, in this travel, the warming of'the material beingtreated actsto effect a shrinkage in the total airvolume,

For maintained draft into the outlets or air escape ducts, and avoidanceof excessive load upon the fan for building up higher'initial pressure,there is automatic compensation herein due to the outlet series of.ducts in each instance beingless capacity than the series of inlet ductssupplying such outletser1es. The drop in air volume due to theshrinkage, thus has no tendency to tolerate back flows from the airescape ducts. There is accordingly approximated a uniform draftpositively through the' material and upward.

What is claimed and it is cure by Letters Patent is:

1'. Inthe drying of coal, the-alternate dividing and combining of agravity flowing stream of the coal to form. angle of repose determinedsurfaces of the coal, taking ofi desired to secles of coal from anotherset of said dividers, a dustcollector to which the discharge ductextends, a discharge duct from the dividers for the coal, and acollected coal duct efromi the dust collector to said coal dischargeduet to fiow the two streams ofcoal together for the material beingdried forming free angle of .repose surfaces as termini for treatingmedium flow therebetween, said duct section termini being carried byrectangular housother closed at said end, said sections having a ingunits for laterally abutting assembly into groupings for multiple ductextent.

4. Drying apparatus comprising a housing embodying open bottom ductcarrying sections as horizontal series of units, adjacent series beingoffset, one of said series beingprovided with gas intake and anotherwith gas escape connections of rectangular bounding extent for laterallyabutting asv,sembly into'section groupings of multiple duct extent;

5. A coal drier embodyinga coal stream subdividing housing, a blower fordirecting air currents through the subdivided stream of coal, a dry coaldelivery way from said .housing, a dust collector for removing entrainedparticles from the air as extracted from the coal, and means forconveying the collected dust from the dust'collector to the dry coaldelivery way forthereby effecting commingling thereof with said stream.

6. A drier embodying similar sections, each comprising an invertedtrough, and rec- 'being a closure for the trough and the other of saidends having an opening in communicationwith said trough, and means forassembling said ends into position for group OLIVER W. RANDOLPH.

tangular supports providing trough ends as an assembled-trough unit, oneof said ends

